Traction devices

ABSTRACT

The present invention provides traction apparatus for wet cloth comprising at least one, horizontally mounted, cylindrical traction roller whose peripheral surface is roughened or knurled for penetrating surface liquor and contacting wet cloth when the latter is fed at least partially around the roller, the peripheral surface of the traction roller being further provided with left and right handed helical grooves for carrying liquor deposited by the cloth on the traction roller towards the ends thereof, and a tensioning device arranged downstream of the traction roller in the direction of movement of cloth driven by the traction roller and adapted to provide an oscillating tension in cloth engaging the traction roller so as to enhance driving contact of the cloth with the traction roller.

United States Patent Dennis [4 Mar. 28, 197 2 [541 TRACTION DEVICES [72] Inventor: George Pollard Dennis, 6 Hilary Mansions, Primary Examiner-An Kmwles Malonie Road, wallasey, England Assistant Examiner-Gene A. Church Attorney-Scrivener, Parker, Scrivener & Clarke [73] Assigneez Pen Croft Dyeing and Printing Co. Limited,

Bury Lancashire, England [57] ABSTRACT [22] Filed: Oct. 15, 1970 The present invention provides traction apparatus for wet cloth comprising at least one, horizontally mounted, cylindri- [211 App! 81367 cal traction roller 'whose peripheral surface is roughened or [30] Foreign Application Pri rit D knurled for penetrating surface liquor and contacting wet v cloth when the latter is fed at least partially around the roller, 0C- 25, Great Brita n ..52,380/ the peripheral surface of the traction roller further provided with left and right handed helical grooves for carrying liquor deposited by the cloth on the traction roller towards the I 58] Field 'g 172 171 ends thereof, and-a tensioning device arranged downstream of 226/182 26/63 6 the traction roller in the direction of movement of cloth driven by the traction roller and adapted to provide an oscillating [56] References Cited tension in cloth engaging the traction roller so as to enhance UNITED ATES PATENTS driving contact of the cloth with the traction roller.

2,952,201 9/1960 Gibson ..226/l90 9 Claims, 4 Drawing Figures PATENTEDM I912 SHEET 1 [IF 2 MGR TRACTION DEVICES The present invention relates to traction devices and in particular to a method and apparatus for use in the mechanical handling of wet or slimy cloth.

Most woven fabrics, such as cotton, are subjected to several chemical-type processes before they can be used by manufacturers for producing goods for sale to consumers. Examples of such processes are scouring, bleaching and dyeing which are intended to remove impurities in the cloth, whiten the cloth or color the cloth respectively, before it reaches the manufacturer. During some of these processes, the cloth is caused to become wet and slimy by the action, for example, of caustic soda solution. When the cloth is in this state, difficulty has been experienced in its handling since known cloth drawing devices do not achieve sufficient grip on the slimy cloth to ensure smooth and continuous traction thereof without undesirably expressing a considerable proportion of the liquor from the cloth that has previously been added to achieve a subsequent chemical process.

According to one aspect of the present invention, traction apparatus for wet cloth comprises at least one, horizontally mounted, cylindrical traction roller whose peripheral surface is roughened or knurled for penetrating surface liquor and contacting wet cloth when the latter is fed at least partially around the roller, the peripheral surface of the traction roller being further provided with left and right handed helical grooves for carrying liquor deposited by the cloth on the traction roller towards the ends thereof, and a tensioning device arranged downstream of the traction roller in the direction of movement of cloth driven by the traction roller and adapted to provide an oscillating tension in cloth engaging the traction roller so as to enhance driving contact of the cloth with the traction roller.

Preferably, there are several such traction rollers, each pair of traction rollers having a guide roller associated therewith to achieve a high area of surface contact of the cloth with each individual traction roller.

The left and right handed helical grooves may extend outwards from the center of the roller to the two ends of the roller respectively or both may extend from one end of the roller to the other. In the latter case, the grooves will obviously intersect one another several times between the roller ends.

According to a second aspect of the invention, a method of drawing wet cloth comprises passing the cloth around at least one driven traction roller whose peripheral surface is roughened or knurled for penetrating surface liquor and contacting the cloth, the peripheral surface of the traction roller being further provided with left and right handed helical grooves for carrying liquor deposited by the cloth on the traction roller towards the ends thereof, and subjecting the cloth to an oscillating tension by means of a tensioning device arranged downstream of the direction of movement of cloth driven by the traction roller so as to enhance driving contact between the cloth and the traction roller.

The invention will be further described, by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic side elevation of one embodiment of traction apparatus constructed in accordance with the present invention;

FIG. 2 is a diagrammatic side elevation of a second embodiment of traction apparatus constructed in accordance with the invention;

FIG. 3 is a diagrammatic side elevation of one embodiment of a knurled and grooved traction roller forming part of the apparatus of the invention; and

FIG. 4 is a diagrammatic side elevation of a second embodiment of a knurled and grooved traction roller.

In the diagrammatic views of FIGS. 1 and 2, a length of slimy cloth 10, such as cotton, is to be drawn in the directions of the arrows A and B respectively, the cloth having previously been subjected in each case to a chemical-type process, illustrated diagrammatically by the boxes 11, such as soaking in caustic soda solution which has resulted in the slimy condition of the cloth. It is now desired to remove the cloth from the caustic soda solution and to transfer it progressively, with a minimum expression of the liquor carried thereby, to a further process 13 where it may be subjected, for example, to heating under pressure in an autoclave. It is for the purpose of transferring the cloth in this manner that the apparatus of the present invention has been devised.

With reference to FIG. 1, the cloth 10 extending from the previous process passes over a series of rollers 12, only one of which is shown, journaled in fixed bearings 12a in order to lead the cloth to the traction apparatus which follows. The traction apparatus includes a pair of drivable traction rollers 14 which are horizontally journaled in respective bearings 14a, 14b so as to be located in juxtaposed relationship with a parallel guide roller 16 which is horizontally journaled in bearings 16a. The drawing means for the traction rollers 14 can be,for example, a motor 15 which drives one of the rollers by means of a belt 17, the rollers 14 being interconnected by means of a further belt 19. The guide roller 16 is spaced from both of the traction rollers 14 to allow cloth to pass therebetween without nipping. Two embodiments of traction rollers 14 are illustrated in more detail in FIGS. 3 and 4.

The embodiment of FIG. 3 comprises a cylindrical metal roller which is provided with left and right handed helical peripheral threads or grooves 18 and 20 extending from the center of the roller to its two ends respectively. The threads are formed in a coarse manner on the roller 14 so that a spirally shaped peripheral area 22 remains. This peripheral area 22 is provided with knurls 24 for the purpose of achieving a great frictional drag on the cloth. In the embodiment of FIG. 4, a cylindrical metal roller 50 is provided with left and right handed, helic al,peripheral grooves 52,54 each of which extends from end to end of the roller. The areas of the peripheral surface of the rollers which are not grooved are roughened or knurled.

The helical grooves may be formed in many other ways. For example, they can be formed by. winding pre-knurled silicon rubber strip, or strips, onto a cylindrical roller.

As shown in FIG. 1, the cloth leaving the roller 12 is passed around the periphery of the first traction roller 14 and over the guide roller 16 where its direction of travel is reversed. It then passes around the periphery of the second traction roller 14, the guide roller 16 ensuring that there is substantial cloth contact with the roller 14. The rollers 14 and 16 are spaced apart to ensure that there is a minimum expression of process liquors from the cloth during its passage around the guide roller. The particular number of rollers 14 employed may be extended as physical conditions dictate. For example, in extreme conditions of lack of space a single roller 14 can be used, whereas if sufficient space is available, a plurality of such rollers 14 may be employed.

The cloth 10 is then passed over one or more rollers 26, horizontally journaled in bearings 26a which lead the cloth to a tensioning device 28. The tensioning device 28 of FIG. 1 comprises two elongate shaft members 36,38 which are rotatable in opposite directions about their longitudinal axes in respective bearings 36a,38by means of a motor 37 and respective belts 36b,38b. Each shaft 36,38 carries a plurality of parallel slats 32,34 respectively, each set of slats 32,34 being radially displaced from its supporting member 36,38 and individual adjacent slats in each set being equally angularly spaced from each other. The length of the slats 32,34 is arranged to be greater than the width of the cloth 10. The spacing of the member 36,38 is such that the paths of movement of the two sets of slats 32,34 intersect whereby a degree of interengagement or meshing of the slats is obtained. The cloth is arranged to pass between the two sets of slats at the region of interengagement as shown in the drawing. The spacing between the members 36,38 is preferably variable to suit the type of cloth and chemical process in use. The angular velocity of the members 36,38 of the tensioning device is ar ranged to be in excess, for example, 20 percent, of the angular velocity of the rollers 14 and 16.

In operation of the apparatus of FIG. 1, a certain amount of traction is achieved by the rollers 14 and the roller 16. This is enhanced by the knurled peripheral portions of the rollers 14. The left and right hand threads or grooves are provided to carry liquids deposited by the cloth on the rollers 14 to the roller ends where the liquid is discharged, the traction surfaces of the rollers 14 thus being maintained in a relatively dry state. If such liquids were not removed but were allowed to build-up on the rollers 14, the knurls would become enveloped in the liquid with an associated reduction in the friction available for traction of the cloth. The effect is aggravated by the fact that frequently the liquid being deposited by the cloth on the rollers 14, is of an extremely viscous nature. However, even such viscous liquids can be successfully removed by the left and right handed screw threads or grooves 20 and 22.

The tensioning device 28, which is driven at a faster speed than the traction rollers as previously described, ensures that the cloth extending from the second roller 14 is subjected to a continuously varying but mainly positive, tension. The device 28 of this embodiment thus provides an oscillating tension or snapping-like action on the cloth after it leaves the second roller 14 whereby to ensure that the traction efi'ect of the rollers l6, 14 is enhanced. One effect of this tension is to cause the cloth to engage in the grooves 18,20 whereby to increase the traction efficiency. The cloth is allowed to drop from the tensioning device 28 directly to the next process. It also allows the cloth to be fed to subsequent processes in a slack or relaxed condition with all creases, folds etc. set up in the traction system removed.

In the embodiment illustrated in FIG. 2 the apparatus is identical except that the tensioning device 28 is replaced by a tensioning device 40 comprising a pair of conveyor belts 42,44 having a plurality of slats 46,48 attached thereto which extend in a direction parallel to the axis of the traction rollers 14. The belts are carried on rollers 42a, 42b, 44a,44b, joumaled in respective bearings 42c, 42d, 44c, 44d, the rollers 42a, 44a being rotated in opposite directions by means of a motor 47 and belts 47a, 47b respectively. The belts are arranged opposite one another so that the slats 46, 48 mesh with one another over a part of their movement when the belts are driven. The cloth is arranged to pass between the two belts 42, 44 at the region of meshing of the slats 46, 48 whereby the cloth 10 is again subjected to a continuously varying tension when the belts are driven at a faster speed than the traction rollers.

In a further embodiment, the slatted belts 42, 44 of FIG. 2 can be replaced by a pair of chains having a plurality of slats attached thereto. Both in the latter embodiment and in that of FIG. 2, both belts or chains are driven together so that they travel at the same speed with the two sets of slats synchronized. Thus, over the meshing region of the slats, any one slat on the belt 44 lies midway between two adjacent slats on the belt 42, this relationship being maintained constant during operation by the coupled drive for the belts or chains.

Adjustment of the tension to which the cloth is subjected by the tensioning devices is provided by enabling the depth of engagement between the two sets of slats to be varied. In the case of the embodiment of FIG. 2, this may be effected by moving one belt or chain carriage laterally towards or away from the other in the pair.

It is also advantageous, in the case of the embodiment of FIG. 2, for the angular relationship between the meshing parts of the belts or chains to be adjustable. This enables there to be a deeper engagement of the slats at the inlet end of the tensioning device and less engagement at the outlet end. Conversely, it can be arranged for there to be greater engagement at the outlet end than at the inlet end.

It is thought that the vibrating tensioning device such as is shown in FIG. 2 has the additional advantage of stroking surface liquors, carried by the cloth and expressed during passage past the rollers 14,16 back into the cloth during its passage through the tensioning device.

The interengaging members of the tensioning device may be formed in many other ways. For example, two parallel cylinmanner of gears.

It is to be noted that the bearings illustrated for the various rollers and shafts and the drives for the traction rollers and tensioning means are drawn in diagrammatic form only. It is also to be noted that although the embodiments of FIGS. 1 and 2 have been described as including separate driving motors 15, 37, 47 for the traction rollers and the two forms of tensioning device respectively, it is convenient in practice for both the tensioning device and the traction rollers, in the case of each embodiment, to be driven by a single motor and a single comprehensive belt, chain or gear transmission system. In these circumstances, the overspeed of the tensioning device can be attained by a suitable selection of the pulleys, sprockets or gear wheels respectively. In all the embodiments described, it is important that the two rotating members comprising the tensioning device between which the cloth is passed are driven together so that they both rotate at the same speed and in synchronised meshing engagement.

As mentioned previously, the above described traction apparatus is suitable for use in continuous autoclave processing wherein at least one such traction device is mounted inside the autoclave to draw cloth into the vessel. The operation of the tensioning device is such that, the cloth emanating therefrom is deposited into the vessel in a released and generally plaited condition, whilst the chemical processes in the autoclave are in operation. This enables a greater quantity of cloth to be handled inside an autoclave of given dimension. In these circumstances, further traction apparatus'may be mounted outside of the autoclave for effecting the removal of the cloth from the autoclave and whereby the cloth can be plaited into a further treatment stage, as required.

1 claim:

1. Traction apparatus for wet cloth comprising, first bearing means;

at least one cylindrical traction roller joumaled horizontally in said first bearing means;

means for rotating said traction roller in said first bearing means;

a roughened peripheral surface on said traction roller for penetrating surface liquor and contacting wet cloth when the latter is fed at least partially around said roller;

left and right handed helical groove in said peripheral surface of the traction roller for carrying liquor deposited by said cloth on the traction roller towards the ends of said roller; and

means located downstream of said traction roller, in the direction of movement of cloth driven by the traction roller, and adapted to provide an ocillating tension in cloth engaging said traction roller.

2. Traction apparatus according to claim 1 in which said left and right handed grooves extend from the center of said traction roller to its two ends respectively.

, 3. Traction apparatus according to claim 2 in which said grooves are formed by winding pre-knurled silicon rubber strip, or strips, onto a cylindrical roller.

4. Traction apparatus according to claim 1 in which both of said left and right handed grooves extend from end to end of said traction roller.

5. Traction apparatus according to claim 1 in which said grooves are formed by machining a cylindrical roller.

6. Traction apparatus according to claim 1 comprising a plurality of said traction rollers joumaled in said first bearing means, a respective parallel guide roller operably-associated with each pair of said traction rollers and which is equally spaced from both of the rollers in said pair so that the cloth can pass over said rollers and around the guide roller without being nipped.

7. Traction apparatus according to claim 1 in which said oscillating tension means comprises second bearing means, two rotatable shafts journaled in said second bearing means so as to be parallel to said traction roller, a respective set of slats mounted on each of said two shafts with the slats in each set parallel to, and radially spaced from, their supporting shaft and with adjacent slats in the set equally angularly spaced from each other, and means for rotating said shafts at an angular velocity in excess of that of said traction roller, the spacing of said shafts being such that the path of movement of said two sets of slats intersect to produce meshing of the slats whereby, when said cloth is passed between said two sets of slats at the region of their interengagement, the cloth is subjected to an oscillating tension.

8. Traction apparatus according to claim 1 in which said oscillating tension means comprises third bearing means, two

sets of rollers journaled in said third bearing means, a pair of conveyor belts operably extending around said two sets of rollers respectively, means for driving said belts at a velocity in excess of the peripheral velocity of said traction roller, a

respective set of slats attached to each of the belts so as to extend in a direction parallel to said traction roller, the belts being arranged such that the slats in each set mesh with one another over a part of their movement when the belts are driven by said driving means whereby, when said cloth is passed between said two belts at the region of meshing of the slats, the cloth is subjected to an oscillating tension.

9. A method of drawing wet cloth comprising passing the cloth around at least one driven traction roller whose peripheral surface is roughened for penetrating surface liquor and contacting the cloth, the peripheral surface of the traction roller being further provided with left and right handed helical grooves for carrying liquor deposited by the cloth on the traction roller towards the ends thereof, and subjecting the cloth to an oscillating tension by means of tensioning means arranged downstream of the direction of movement of cloth driven by the traction roller so as to enhance driving contact between the cloth and the traction roller.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,652,002 Dated March 28, 1972 Inventor(s) George Pollard Dennis It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the cover sheet [73] "Pen Croft Dyeing and Printing Co., Limited," should read Pin Croft Dyeing and Printing Co. Limited Signed and sealed this 12th day of December 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. "ROBERT GOT'ISCHALK Attesting Officer Commissioner of Patents FORM P0-1 uscoMM-Dc 60376-P69 I U.S. GOVERNMENT PRINTING OFFICE: IQID 0-856-33, 

1. Traction apparatus for wet cloth comprising, first bearing means; at least one cylindrical traction roller journalled horizontally in said first bearing means; means for rotating said traction roller in said first bearing means; a roughened peripheral surface on said traction roller for penetrating surface liquor and contacting wet cloth when the latter is fed at least partially around said roller; left and right handed helical groove in said peripheral surface of the traction roller for carrying liquor deposited by said cloth on the traction roller towards the ends of said roller; and means located downstream of said traction roller, in the direction of movement of cloth driven by the traction roller, and adapted to provide an ocillating tension in cloth engaging said traction roller.
 2. Traction apparatus according to claim 1 in which said left and right handed grooves extend from the center of said traction roller to its two ends respectively.
 3. Traction apparatus according to claim 2 in which said grooves are formed by winding pre-knurled silicon rubber strip, or strips, onto a cylindrical roller.
 4. Traction apparatus according to claim 1 in which both of said left and right handed grooves extend from end to end of said traction roller.
 5. Traction apparatus according to claim 1 in which said grooves are formed by machining a cylindrical roller.
 6. Traction apparatus according to claim 1 comprising a plurality of said traction rollers journalled in said first bearing means, a respective parallel guide roller operably-associated with each pair of said traction rollers and which is equally spaced from both of the rollers in said pair so that the cloth can pass over said rollers and around the guide roller without being nipped.
 7. Traction apparatus according to claim 1 in which said oscillating tension means comprises second bearing means, two rotatable shafts journalled in said second bearing means so as to be parallel to said traction roller, a respective set of slats mounted on each of said two shafts with the slats in each set parallel to, and radially spaced from, their supporting shaft and with adjacent slats in the set equally angularly spaced from each other, and means for rotating said shafts at an angular velocity in excess of that of said traction roller, the spacing of said shafts being such that the path of movement of said two sets of slats intersect to produce meshing of the slats whereby, when said cloth is passed between said two sets of slats at the region of their interengagement, the cloth is subjected to an oscillating tension.
 8. Traction apparatus according to claim 1 in which said oscillating tension means comprises third bearing means, two sets of rollers journalled in said third bearing means, a pair of conveyor belts operably extending around said two sets of rollers respectively, means for driving said belts at a velocity in excess of the peripheral velocity of said traction roller, a respective set of slats attached to each of the belts so as to extend in a direction parallel to said traction roller, the belts being arranged such that the slats in each set mesh with one another over a part of their movement when the belts are driven by said driving means whereby, when said cloth is passed between said two belts at the region of meshing of the slats, the cloth is subjected to an oscillating tension.
 9. A method of drawing wet cloth comprising passing the cloth around at least one driven traction roller whose peripheral surface is roughened for penetrating surface liquor and contacting the cloth, the peripheral surface of the traction roller being further provided with leFt and right handed helical grooves for carrying liquor deposited by the cloth on the traction roller towards the ends thereof, and subjecting the cloth to an oscillating tension by means of tensioning means arranged downstream of the direction of movement of cloth driven by the traction roller so as to enhance driving contact between the cloth and the traction roller. 